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Henk M, Hilson C, Bean WT, Barton DC, Gunther MS. Noninvasive genetic sampling with a spatial capture‐recapture analysis to estimate abundance of Roosevelt elk. J Wildl Manage 2022. [DOI: 10.1002/jwmg.22294] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Makenzie Henk
- Department of Wildlife California State Polytechnic University, Humboldt, 1 Harpst Street Arcata CA 95521 USA
| | - Carrington Hilson
- California Department of Fish and Wildlife, 619 2nd Street Eureka CA 95501 USA
| | - William T. Bean
- Department of Wildlife California State Polytechnic University, Humboldt, 1 Harpst Street Arcata CA 95521 USA
| | - Daniel C. Barton
- Department of Wildlife California State Polytechnic University, Humboldt, 1 Harpst Street Arcata CA 95521 USA
| | - Micaela Szykman Gunther
- Department of Wildlife California State Polytechnic University, Humboldt, 1 Harpst Street Arcata CA 95521 USA
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Brandell EE, Cross PC, Smith DW, Rogers W, Galloway N, MacNulty DR, Stahler DR, Treanor J, Hudson PJ. Examination of the interaction between age-specific predation and chronic disease in the Greater Yellowstone Ecosystem. J Anim Ecol 2022; 91:1373-1384. [PMID: 34994978 PMCID: PMC9912199 DOI: 10.1111/1365-2656.13661] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Accepted: 12/28/2021] [Indexed: 11/27/2022]
Abstract
Predators may create healthier prey populations by selectively removing diseased individuals. Predators typically prefer some ages of prey over others, which may, or may not, align with those prey ages that are most likely to be diseased. The interaction of age-specific infection and predation has not been previously explored and likely has sizable effects on disease dynamics. We hypothesize that predator cleansing effects will be greater when the disease and predation occur in the same prey age groups. We examine the predator cleansing effect using a model where both vulnerability to predators and pathogen prevalence vary with age. We tailor this model to chronic wasting disease (CWD) in mule deer and elk populations in the Greater Yellowstone Ecosystem, with empirical data from Yellowstone grey wolves and cougars. Model results suggest that under moderate, yet realistic, predation pressure from cougars and wolves independently, predators may decrease CWD outbreak size substantially and delay the accumulation of symptomatic deer and elk. The magnitude of this effect is driven by the ability of predators to selectively remove late-stage CWD infections that are likely the most responsible for transmission, but this may not be the age class they typically select. Thus, predators that select for infected young adults over uninfected juveniles have a stronger cleansing effect, and these effects are strengthened when transmission rates increase with increasing prey morbidity. There are also trade-offs from a management perspective-that is, increasing predator kill rates can result in opposing forces on prey abundance and CWD prevalence. Our modelling exploration shows that predators have the potential to reduce prevalence in prey populations when prey age and disease severity are considered, yet the strength of this effect is influenced by predators' selection for demography or body condition. Current CWD management focuses on increasing cervid hunting as the primary management tool, and our results suggest predators may also be a useful tool under certain conditions, but not necessarily without additional impacts on host abundance and demography. Protected areas with predator populations will play a large role in informing the debate over predator impacts on disease.
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Affiliation(s)
- Ellen E. Brandell
- Center for Infectious Disease Dynamics and Department of Biology, Huck Institutes of the Life SciencesPennsylvania State UniversityUniversity ParkPAUSA,Wisconsin Cooperative Wildlife Research Unit, Department of Forest and Wildlife EcologyUniversity of Wisconsin‐MadisonMadisonWIUSA
| | - Paul C. Cross
- U.S. Geological SurveyNorthern Rocky Mountain Science CenterBozemanMTUSA
| | - Douglas W. Smith
- Yellowstone Center for ResourcesYellowstone National ParkWyomingWYUSA
| | - Will Rogers
- Department of EcologyMontana State UniversityBozemanMTUSA
| | | | | | - Daniel R. Stahler
- Yellowstone Center for ResourcesYellowstone National ParkWyomingWYUSA
| | - John Treanor
- Yellowstone Center for ResourcesYellowstone National ParkWyomingWYUSA
| | - Peter J. Hudson
- Center for Infectious Disease Dynamics and Department of Biology, Huck Institutes of the Life SciencesPennsylvania State UniversityUniversity ParkPAUSA
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3
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Elk Responses to Management Hunting and Hazing. J Wildl Manage 2021. [DOI: 10.1002/jwmg.22113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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4
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Szcodronski KE, Cross PC. Scavengers reduce potential brucellosis transmission risk in the Greater Yellowstone Ecosystem. Ecosphere 2021. [DOI: 10.1002/ecs2.3783] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Affiliation(s)
| | - Paul C. Cross
- Northern Rocky Mountain Science Center U.S. Geological Survey Bozeman Montana 59715 USA
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5
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Rayl ND, Merkle JA, Proffitt KM, Almberg ES, Jones JD, Gude JA, Cross PC. Elk migration influences the risk of disease spillover in the Greater Yellowstone Ecosystem. J Anim Ecol 2021; 90:1264-1275. [PMID: 33630313 PMCID: PMC8251637 DOI: 10.1111/1365-2656.13452] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2019] [Accepted: 11/16/2020] [Indexed: 11/30/2022]
Abstract
Wildlife migrations provide important ecosystem services, but they are declining. Within the Greater Yellowstone Ecosystem (GYE), some elk Cervus canadensis herds are losing migratory tendencies, which may increase spatiotemporal overlap between elk and livestock (domestic bison Bison bison and cattle Bos taurus), potentially exacerbating pathogen transmission risk. We combined disease, movement, demographic and environmental data from eight elk herds in the GYE to examine the differential risk of brucellosis transmission (through aborted foetuses) from migrant and resident elk to livestock. For both migrants and residents, we found that transmission risk from elk to livestock occurred almost exclusively on private ranchlands as opposed to state or federal grazing allotments. Weather variability affected the estimated distribution of spillover risk from migrant elk to livestock, with a 7%–12% increase in migrant abortions on private ranchlands during years with heavier snowfall. In contrast, weather variability did not affect spillover risk from resident elk. Migrant elk were responsible for the majority (68%) of disease spillover risk to livestock because they occurred in greater numbers than resident elk. On a per‐capita basis, however, our analyses suggested that resident elk disproportionately contributed to spillover risk. In five of seven herds, we estimated that the per‐capita spillover risk was greater from residents than from migrants. Averaged across herds, an individual resident elk was 23% more likely than an individual migrant elk to abort on private ranchlands. Our results demonstrate links between migration behaviour, spillover risk and environmental variability, and highlight the utility of integrating models of pathogen transmission and host movement to generate new insights about the role of migration in disease spillover risk. Furthermore, they add to the accumulating body of evidence across taxa that suggests that migrants and residents should be considered separately during investigations of wildlife disease ecology. Finally, our findings have applied implications for elk and brucellosis in the GYE. They suggest that managers should prioritize actions that maintain spatial separation of elk and livestock on private ranchlands during years when snowpack persists into the risk period.
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Affiliation(s)
- Nathaniel D Rayl
- Colorado Parks and Wildlife, Grand Junction, CO, USA.,U.S. Geological Survey, Northern Rocky Mountain Science Center, Bozeman, MT, USA
| | - Jerod A Merkle
- Department of Zoology and Physiology, University of Wyoming, Laramie, WY, USA
| | | | | | | | | | - Paul C Cross
- U.S. Geological Survey, Northern Rocky Mountain Science Center, Bozeman, MT, USA
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6
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Rayl ND, Proffitt KM, Almberg ES, Jones JD, Merkle JA, Gude JA, Cross PC. Modeling elk‐to‐livestock transmission risk to predict hotspots of brucellosis spillover. J Wildl Manage 2019. [DOI: 10.1002/jwmg.21645] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Nathaniel D. Rayl
- U.S. Geological SurveyNorthern Rocky Mountain Science CenterBozemanMT59715USA
| | | | | | | | - Jerod A. Merkle
- Wyoming Cooperative Fish and Wildlife Research UnitDepartment of Zoology and PhysiologyUniversity of WyomingLaramieWY82071USA
| | | | - Paul C. Cross
- U.S. Geological SurveyNorthern Rocky Mountain Science CenterBozemanMT59715USA
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Cotterill GG, Cross PC, Cole EK, Fuda RK, Rogerson JD, Scurlock BM, du Toit JT. Winter feeding of elk in the Greater Yellowstone Ecosystem and its effects on disease dynamics. Philos Trans R Soc Lond B Biol Sci 2019. [PMID: 29531148 PMCID: PMC5882999 DOI: 10.1098/rstb.2017.0093] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Providing food to wildlife during periods when natural food is limited results in aggregations that may facilitate disease transmission. This is exemplified in western Wyoming where institutional feeding over the past century has aimed to mitigate wildlife–livestock conflict and minimize winter mortality of elk (Cervus canadensis). Here we review research across 23 winter feedgrounds where the most studied disease is brucellosis, caused by the bacterium Brucella abortus. Traditional veterinary practices (vaccination, test-and-slaughter) have thus far been unable to control this disease in elk, which can spill over to cattle. Current disease-reduction efforts are being guided by ecological research on elk movement and density, reproduction, stress, co-infections and scavengers. Given the right tools, feedgrounds could provide opportunities for adaptive management of brucellosis through regular animal testing and population-level manipulations. Our analyses of several such manipulations highlight the value of a research–management partnership guided by hypothesis testing, despite the constraints of the sociopolitical environment. However, brucellosis is now spreading in unfed elk herds, while other diseases (e.g. chronic wasting disease) are of increasing concern at feedgrounds. Therefore experimental closures of feedgrounds, reduced feeding and lower elk populations merit consideration. This article is part of the theme issue ‘Anthropogenic resource subsidies and host–parasite dynamics in wildlife’.
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Affiliation(s)
- Gavin G Cotterill
- Department of Wildland Resources, Utah State University, 5230 Old Main Hill, Logan, UT 84322, USA
| | - Paul C Cross
- U.S. Geological Survey, Northern Rocky Mountain Science Center, 2327 University Way, Suite 2, Bozeman, MT 59715, USA
| | - Eric K Cole
- U.S. Fish and Wildlife Service, National Elk Refuge, PO Box 510, Jackson, WY 83001, USA
| | - Rebecca K Fuda
- Wyoming Game and Fish Department, 432 Mill Street, Pinedale, WY 82941, USA
| | - Jared D Rogerson
- Wyoming Game and Fish Department, 432 Mill Street, Pinedale, WY 82941, USA
| | - Brandon M Scurlock
- Wyoming Game and Fish Department, 432 Mill Street, Pinedale, WY 82941, USA
| | - Johan T du Toit
- Department of Wildland Resources, Utah State University, 5230 Old Main Hill, Logan, UT 84322, USA
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Painter LE, Beschta RL, Larsen EJ, Ripple WJ. Aspen recruitment in the Yellowstone region linked to reduced herbivory after large carnivore restoration. Ecosphere 2018. [DOI: 10.1002/ecs2.2376] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Affiliation(s)
- Luke E. Painter
- Department of Fisheries and Wildlife; Oregon State University; Corvallis Oregon 97331 USA
| | - Robert L. Beschta
- Department of Forest Ecosystems and Society; Oregon State University; Corvallis Oregon 97331 USA
| | - Eric J. Larsen
- Department of Geography and Geology; University of Wisconsin-Stevens Point; Stevens Point Wisconsin 54481-3897 USA
| | - William J. Ripple
- Department of Forest Ecosystems and Society; Oregon State University; Corvallis Oregon 97331 USA
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Brennan A, Cross PC, Portacci K, Scurlock BM, Edwards WH. Shifting brucellosis risk in livestock coincides with spreading seroprevalence in elk. PLoS One 2017; 12:e0178780. [PMID: 28609437 PMCID: PMC5469469 DOI: 10.1371/journal.pone.0178780] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2016] [Accepted: 05/18/2017] [Indexed: 11/18/2022] Open
Abstract
Tracking and preventing the spillover of disease from wildlife to livestock can be difficult when rare outbreaks occur across large landscapes. In these cases, broad scale ecological studies could help identify risk factors and patterns of risk to inform management and reduce incidence of disease. Between 2002 and 2014, 21 livestock herds in the Greater Yellowstone Area (GYA) were affected by brucellosis, a bacterial disease caused by Brucella abortus, while no affected herds were detected between 1990 and 2001. Using a Bayesian analysis, we examined several ecological covariates that may be associated with affected livestock herds across the region. We showed that livestock risk has been increasing over time and expanding outward from the historical nexus of brucellosis in wild elk on Wyoming’s feeding grounds where elk are supplementally fed during the winter. Although elk were the presumed source of cattle infections, occurrences of affected livestock herds were only weakly associated with the density of seropositive elk across the GYA. However, the shift in livestock risk did coincide with recent increases in brucellosis seroprevalence in unfed elk populations. As increasing brucellosis in unfed elk likely stemmed from high levels of the disease in fed elk, disease-related costs of feeding elk have probably been incurred across the entire GYA, rather than solely around the feeding grounds. Our results suggest that focused disease mitigation in areas where seroprevalence in unfed elk is high could reduce the spillover of brucellosis to livestock. We also highlight the need to better understand the epidemiology of spillover events with detailed histories of disease testing, calving, and movement of infected livestock. Finally, we recommend using case-control studies to investigate local factors important to livestock risk.
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Affiliation(s)
- Angela Brennan
- Wyoming Cooperative Fish and Wildlife Research Unit, Department of Zoology and Physiology, University of Wyoming, Laramie, Wyoming, United States of America
- U.S. Geological Survey, Northern Rocky Mountain Science Center, Bozeman, Montana, United States of America
- * E-mail:
| | - Paul C. Cross
- U.S. Geological Survey, Northern Rocky Mountain Science Center, Bozeman, Montana, United States of America
| | - Katie Portacci
- U.S. Department of Agriculture, Animal and Plant Health Inspection Service-Centers for Epidemiology and Animal Health, Fort Collins, Colorado, United States of America
| | - Brandon M. Scurlock
- Wyoming Game and Fish Department, Pinedale, Wyoming, United States of America
| | - William H. Edwards
- Wyoming Game and Fish Department, Laramie, Wyoming, United States of America
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10
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Morris LR, Blackburn JK. Predicting Disease Risk, Identifying Stakeholders, and Informing Control Strategies: A Case Study of Anthrax in Montana. ECOHEALTH 2016; 13:262-73. [PMID: 27169560 PMCID: PMC5965262 DOI: 10.1007/s10393-016-1119-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2015] [Revised: 03/14/2016] [Accepted: 03/17/2016] [Indexed: 06/05/2023]
Abstract
Infectious diseases that affect wildlife and livestock are challenging to manage and can lead to large-scale die-offs, economic losses, and threats to human health. The management of infectious diseases in wildlife and livestock is made easier with knowledge of disease risk across space and identifying stakeholders associated with high-risk landscapes. This study focuses on anthrax, caused by the bacterium Bacillus anthracis, risk to wildlife and livestock in Montana. There is a history of anthrax in Montana, but the spatial extent of disease risk and subsequent wildlife species at risk are not known. Our objective was to predict the potential geographic distribution of anthrax risk across Montana, identify wildlife species at risk and their distributions, and define stakeholders. We used an ecological niche model to predict the potential distribution of anthrax risk. We overlaid susceptible wildlife species distributions and land ownership delineations on our risk map. We found that there was an extensive region across Montana predicted as potential anthrax risk. These potentially risky landscapes overlapped the ranges of all 6 ungulate species considered in the analysis and livestock grazing allotments, and this overlap was on public and private land for all species. Our findings suggest that there is the potential for a multi-species anthrax outbreak on multiple landscapes across Montana. Our potential anthrax risk map can be used to prioritize landscapes for surveillance and for implementing livestock vaccination programs.
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Affiliation(s)
- Lillian R Morris
- Spatial Epidemiology & Ecology Research Laboratory, Department of Geography, University of Florida, 3141 Turlington Hall, PO Box 117315, Gainesville, FL, 32611-7315, USA.
- Emerging Pathogens Institute, University of Florida, 2055 Mowry Road, Gainesville, FL, 32611, USA.
| | - Jason K Blackburn
- Spatial Epidemiology & Ecology Research Laboratory, Department of Geography, University of Florida, 3141 Turlington Hall, PO Box 117315, Gainesville, FL, 32611-7315, USA
- Emerging Pathogens Institute, University of Florida, 2055 Mowry Road, Gainesville, FL, 32611, USA
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11
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Kamath PL, Foster JT, Drees KP, Luikart G, Quance C, Anderson NJ, Clarke PR, Cole EK, Drew ML, Edwards WH, Rhyan JC, Treanor JJ, Wallen RL, White PJ, Robbe-Austerman S, Cross PC. Genomics reveals historic and contemporary transmission dynamics of a bacterial disease among wildlife and livestock. Nat Commun 2016; 7:11448. [PMID: 27165544 PMCID: PMC4865865 DOI: 10.1038/ncomms11448] [Citation(s) in RCA: 74] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2015] [Accepted: 03/29/2016] [Indexed: 01/09/2023] Open
Abstract
Whole-genome sequencing has provided fundamental insights into infectious disease epidemiology, but has rarely been used for examining transmission dynamics of a bacterial pathogen in wildlife. In the Greater Yellowstone Ecosystem (GYE), outbreaks of brucellosis have increased in cattle along with rising seroprevalence in elk. Here we use a genomic approach to examine Brucella abortus evolution, cross-species transmission and spatial spread in the GYE. We find that brucellosis was introduced into wildlife in this region at least five times. The diffusion rate varies among Brucella lineages (∼3 to 8 km per year) and over time. We also estimate 12 host transitions from bison to elk, and 5 from elk to bison. Our results support the notion that free-ranging elk are currently a self-sustaining brucellosis reservoir and the source of livestock infections, and that control measures in bison are unlikely to affect the dynamics of unrelated strains circulating in nearby elk populations.
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Affiliation(s)
- Pauline L Kamath
- U.S. Geological Survey, Northern Rocky Mountain Science Center, Bozeman, Montana 59715, USA
| | - Jeffrey T Foster
- Center for Microbial Genetics and Genomics, Northern Arizona University, Flagstaff, Arizona 86011, USA
| | - Kevin P Drees
- Center for Microbial Genetics and Genomics, Northern Arizona University, Flagstaff, Arizona 86011, USA
| | - Gordon Luikart
- Flathead Lake Biological Station, Division of Biological Sciences, University of Montana, Missoula, Montana 59812, USA
| | - Christine Quance
- USDA-APHIS, National Veterinary Services Laboratories, Ames, Iowa 50010, USA
| | - Neil J Anderson
- Montana Fish Wildlife and Parks, Bozeman, Montana 59718, USA
| | - P Ryan Clarke
- USDA-APHIS, Veterinary Services, Fort Collins, Colorado 80526, USA
| | - Eric K Cole
- USFWS, National Elk Refuge, Jackson, Wyoming 83001, USA
| | - Mark L Drew
- Wildlife Health Laboratory, Idaho Department of Fish and Game, Caldwell, Idaho 83607, USA
| | | | - Jack C Rhyan
- USDA-APHIS, Veterinary Services, Fort Collins, Colorado 80526, USA
| | - John J Treanor
- National Park Service, Yellowstone National Park, Mammoth, Wyoming 82190, USA
| | - Rick L Wallen
- National Park Service, Yellowstone National Park, Mammoth, Wyoming 82190, USA
| | - Patrick J White
- National Park Service, Yellowstone National Park, Mammoth, Wyoming 82190, USA
| | | | - Paul C Cross
- U.S. Geological Survey, Northern Rocky Mountain Science Center, Bozeman, Montana 59715, USA
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12
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Brennan A, Cross PC, Creel S. Managing more than the mean: using quantile regression to identify factors related to large elk groups. J Appl Ecol 2015; 52:1656-1664. [PMID: 27660373 PMCID: PMC5016784 DOI: 10.1111/1365-2664.12514] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2015] [Accepted: 07/23/2015] [Indexed: 11/30/2022]
Abstract
Animal group size distributions are often right-skewed, whereby most groups are small, but most individuals occur in larger groups that may also disproportionately affect ecology and policy. In this case, examining covariates associated with upper quantiles of the group size distribution could facilitate better understanding and management of large animal groups.We studied wintering elk groups in Wyoming, where group sizes span several orders of magnitude, and issues of disease, predation and property damage are affected by larger group sizes. We used quantile regression to evaluate relationships between the group size distribution and variables of land use, habitat, elk density and wolf abundance to identify conditions important to larger elk groups.We recorded 1263 groups ranging from 1 to 1952 elk and found that across all quantiles of group size, group sizes were larger in open habitat and on private land, but the largest effect occurred between irrigated and non-irrigated land [e.g. the 90th quantile group size increased by 135 elk (95% CI = 42, 227) on irrigation].Only upper quantile group sizes were positively related to broad-scale measures of elk density and wolf abundance. For wolf abundance, this effect was greater on elk groups found in open habitats and private land than those in closed habitats or public land. If we had limited our analysis to mean or median group sizes, we would not have detected these effects. Synthesis and applications. Our analysis of elk group size distributions using quantile regression suggests that private land, irrigation, open habitat, elk density and wolf abundance can affect large elk group sizes. Thus, to manage larger groups by removal or dispersal of individuals, we recommend incentivizing hunting on private land (particularly if irrigated) during the regular and late hunting seasons, promoting tolerance of wolves on private land (if elk aggregate in these areas to avoid wolves) and creating more winter range and varied habitats. Relationships to the variables of interest also differed by quantile, highlighting the importance of using quantile regression to examine response variables more completely to uncover relationships important to conservation and management.
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Affiliation(s)
- Angela Brennan
- Institute on Ecosystems Montana State University Bozeman MT 59717 USA
| | - Paul C Cross
- U.S. Geological Survey Northern Rocky Mountain Science Center Bozeman MT 59715 USA
| | - Scott Creel
- Department of Ecology Montana State University Bozeman MT 59717 USA
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